The old wives tale is that on their 2nd birthday, you double their height and that is how tall they will be. It has worked rather well with the first 4 but #5 is much taller than it worked out to be. We will see what the rest of them work out to be.

It only works with boys--you double their height at 2 yrs old and that is supposed to be their height at adulthood. However, My brother--who is 20 yrs old--was supposed to be 6'1" and he is 6'5" so it can't be right for everyone.

To some extent yes. The best predictor of a child's adult height is to look at mom and dad and take an average. If parents had healthy lives (meaning there was no reason to believe thier growth was stunted during childhood by illness or poor diet) then their offspring will reflect thier height. You can find various formulas to calculate this on the internet. The bottom line, if mom and dad are geneticly tall or short, baby will be also. Weight is alot trickier because there are so many environmental variations than can cause changes. As for breastfed babies being smaller, that is not true either. My doctor said i make Haagen das milk because my exclusively breast fed baby is in the 98% for height and weight (I am 6'1" and my husband is 6'3").

It's absolutely untrue. My oldest was typically no higher than 25% on height and 10% on weight through age 2, at which time the pediatrician said he was going to be petite (I am petite, so I guess he assumed he got his lack of size from me). That son just turned 15 and is 6'3" tall and weighs about 155. So, he is still quite thin, but the petite thing is laughable. One huge factor is whether or not you breastfeed, since breastfed babies typically gain at a slower rate (brain development exceed muscle development in humans versus cows). The charts are produced by the companies that make the formula (just another way for them to push formula over BF, since BF mothers may feel their babies aren't gaining properly and supplement).